Used as a photoswitchable ligand in supramolecular chemistry and catalysis. Its azo group undergoes reversible trans-cis isomerization upon light exposure, enabling control over molecular assembly and binding affinity. Applied in light-responsive materials, such as smart surfaces and molecular machines. Also employed in the design of photo-regulated metal-organic frameworks (MOFs) due to its carboxylic acid groups that coordinate with metal ions, allowing construction of architectures with tunable porosity and function.